Health Facts

Nearly one in three U.S. adults has high blood pressure. Often called "the silent killer" because it usually has no symptoms, high blood pressure can go undetected for years until problems develop with the heart, brain or kidneys. If not treated, high blood pressure can lead to stroke, blindness, heart attack, heart failure or kidney failure. While the exact causes of hypertension are not known, the only way to tell if you have high blood pressure is to have your blood pressure checked regularly by your doctor.

As oxygen-rich blood is pumped from the heart to all parts of the body, pressure is created as the force of the blood presses against the walls of the arteries. If you're healthy, your arteries are muscular and elastic, and will stretch when your heart pumps blood through them. Your blood pressure is at its highest when the heart beats, forcing the blood through the arteries. This is called systolic pressure. When the heart is between beats, your blood pressure falls. This is the diastolic pressure. A blood pressure measurement is always given using these two numbers; with the systolic pressure (the top number) preceding the diastolic pressure (the bottom number). A normal blood pressure reading of 120/80mmHg is considered normal. While a lower reading is better, very low blood pressures can also be a cause for concern. Blood pressure rises when you get up, and responds minute by minute to the daily affects of emotional stress or exercise, or whether you are sitting or standing still. Because of these normal variations throughout the day, doctors take repeated measurements to diagnose high blood pressure. Blood pressure that stays between 120-139/80-89 mmHg is considered pre-hypertension and above this level (140/90 mmHg or higher) is considered high blood pressure or hypertension. With a higher blood pressure, your heart works harder, your arteries take a pounding, and your chances of a stroke, heart attack, blindness, or kidney problems are greater.